Homo Floresiensis in Human Evolution - Essay Example

?Homo Floresiensis (LB1) in Human Evolution and Related Controversies One of the most spectacular discoveries in paleoanthropology is theunearthing of the species, Homo floresienses, which is believed to be the most severe form of human ever discovered. This paper gives an insight into issues related to Homo floresiensis. First of all, an introduction has been given as to what it is and where it was discovered. Its evolution and the discovery of LB1 have been taken into account. After that, the controversies that have been rising since the unearthing of LB1 specimen have been discussed in detail. The paper is summarized in a concluding paragraph and Harvard referencing style has been used properly. 2. Introduction to the Hobbit Before going into the details of the subject matter, let’s first get to understand what Homo floresiensis actually is. Homo floresiensis, literally meaning Man of Flores, was discovered by Michael Moore’s team at the Liang Bua cave1 on the island of Flores in Indonesia2 on September 2003. Nicknamed as the Hobbit, it is believed to be a species known for its small sized body and brain whose fossils, according to archeologists, have been found somewhere 38,000 to 18,000 years ago3. More specifically speaking, the size is said to be “only about 1 meter in height and fully bipedal, with a very small brain size of 417cc”4. Homo floresiensis may be called contemporaries of Homo sapiens. Scientists suggest that since it is usual that large mammals may exist on islands in their dwarf form, hence Homo floresiensis may also be a dwarf form of Homo erectus. Mayell5 states that the skulls of the tiny humans were the size of grapefruits and they lived on pygmy elephants, Komodo dragons, and big rats found on the island. 3. Homo Floresiensis (LB1) in Human Evolution 3.1. LB1 LB1 is the one complete-most Homo floresiensis fossil that consists of a complete skull and skeleton found by the discoverer team consisting of Australian and Indonesian paleoanthropologists and archaeologists who went to Flores to find out when and how the Homo sapiens migrated from Asia into Australia crossing the sea barriers. Since they were not prepared to find specimen of a new species, they were surprised to find fossils and remains of non Homo sapiens as old as 38,000 years. The found specimen, LB1, contains leg bones, hands, feet, pelvis, and other remains which are both primitive and derived. LB1 is said to be the fossil of an adult who might be the age of 30. An analysis of its pelvis revealed that it was the skeleton of a female. It would have been a bit larger on size if it was a male although all fossil found so far are of the same size as LB1. Since, the individual was of young age, the bones of the skeleton had not fossilized as yet and are reported to be in the consistency of mashed potatoes or wet blotting paper. The brain size is as small as 380cc that is a chimpanzee’s brain’s size. With the fossils of LB1, some stone tools were also found which a homini with such a small sized brain cannot make. Thus the tools are believed to be created by Homo sapiens. Anthropologists, for example, Peter Brown, Michael Morwood and their colleagues argue about LB1 that “it was contemporaneous with modern humans (Homo sapiens) on Flores”6. 3.2. Evolution Homo floresiensis are said to have evolved from Homo erectus and the result is a tremendous decrease in the body and brain size. Because of the reduced brain size, archeologists also suggest that the “floresiensis might actually have evolved from something smaller, such as the Dmanisi hominids found in Georgia, some of which have brain sizes between 600 and 700 cc, smaller than the 800-900cc typical of early erectus”7. Also, when stone tools were found on another location in Flores in 1998, it was said that these tools may be the creation of Homo erectus because these were the pre-sapiens hominids existing in Indonesia who are thought to have crossed the sea-passage that separates Flores from Java. Some archeologists believe that these were not Homo erectus but Dmanisi hominids or an early evolutionary form of Homo floresiensis. Scientists believe that the discovery and study of Homo floresiensis will not at all the evolutionary history of Homo sapiens as the later is surely not descending from the former. However, we cannot deny the fact that since LB1 type species that has been found on the island of Flores resembles human form and can be said as one of the most severe instances of Homo sapiens, hence Homo sapiens are apt to go through some sort of evolution to have taken the form of the tiny hominids. 4. The Controversies The discovery of the Homo florsiensis brought with it man controversies. Whether it should be considered as a new species has been the most controversial issue in this regard. This controversy was initially put forward by an Indonesian knowledgeable anthropologist, Professor Teuku Jacob of Gadjah Mada University of Indonesia, who claimed that the analysis of LB1 skull shows that LB1 was a modern Homo sapien suffering from microcephaly8 which is “a disease that causes small brain sizes”9. Thus, Jacob argued that LB1 could not be considered as a new species, but can be regarded as a “member of the "Australomelanesid race" of modern humans, and only 1,300 to 1,800 years old”10. Jacob insisted that the find belonged to the omnivorous species of Homo sapiens and was an individual of age lower than 30. According to Jacob, the small skull of LB1 might belong to a mentally abnormal individual or a microcephalic Pygmy. The anatomist, Maciej Henneberg, has also supported this statement. However, Brown et al.11 have contradicted the statement and have suggested that although there is a possibility that a human being may come up as a dwarf because of diseases like microcephaly causing reduction in body and brain sizes, still it is not acceptable that the tiny hominids of Flores were microcephalic humans. According to them, when a human being has microcephaly, then there are very few chances that he will reach adulthood while LB1 was the skeleton of an adult. LB1 has archaic traits that are not found with microcephalic humans but are replicated in early hominids. There are many other specimens from Flores who have the same features as archaic traits in the skeletons, and it is not acceptable that such a wide number of microcephalic humans many have evolved in an island. Hence, according to Brown et al., Homo Floresiensis are not just a form of Homo sapiens, but a different species. In 2005, a study was conducted under the supervision of Dean Falk12 who created a CT scan of LB1’s skull and produced a computer generated model. It also showed that the Homo florsiensis were a new species as the skull analysis gave no proof that it belonged to a malformed skull or a microcephalic brain. This study was also contradicted by another research conducted by Weber, Czarnetzki and Pusch13 who affirmed that it was not a new species but microcephalic Homo sapiens. Many researchers have also conducted their researches upon solving this controversy, and most of them have to the conclusion that the researchers, who call LB1 a microcephalic Homo sapiens, have not actually compared the LB1 skull with that of a real microcephalic skull because LB1 brain size was much smaller than that of a microcephalic brain. For LB1 brain size, the size of the whole skeleton should also have been much smaller if it was just a microcephalic being. In 200614 and 200715, Dean Falk, despite all contradictions upon his study, still insisted that the bone and skeletal structure of LB1 were of a diseased modern human. Hershkovitz et al.16 raised another controversy arguing that LB1’s morphological features show that it was a human being with Laron syndrome, a research that Falk et al.17 have rejected in their study concluding that “the type Specimen (LB1) of Homo ?oresiensis did not have Laron Syndrome.” 5. Conclusion The unearthing of Homo floresiensis has brought with it many questions regarding whether it should be considered as a new species that might have evolved on the island of Flores, or should be regarded as an ancestor of Homo sapiens or they might be diseased Homo sapiens. Many researchers have conducted studies on the specimen of LB1, analyzing the bone and skull structure and brain size, producing computer generated images of the brain and comparing it with microcephalic instances from humans. Some consider it an evolved form of Homo erectus; some regard it as descendants of Dmanisi hominids; and, some argue that they are an extreme form of modern day human beings that might have migrated to the island of Flores crossing the sea passage. Despite all the efforts to uncover the truth, the controversies and contradictions still remain and the question regarding the evolution of the Hobbit is still to be answered. (Note for the Admin: the word count is equal to 6 pages excluding the footnotes.) References Brown, P, Sutikna, T, Morwood, M, Soejono, RP, Jatmiko, SEW et al. 2004, ‘A new small-bodied hominin from the late Pleistocene of Flores, Indonesia’. Nature, vol. 431, pp. 1055-1061. Falk, D, Hildebolt, C, Smith, K, Morwood, MJ, Sutikna, T, Brown, P, Jatmiko, WSE, Brunsden, B & Prior, F 2005, ‘The brain of LB1, Homo floresiensis’, Science, vol. 308, no. 5719, p. 242. Falk, D, Hildebolt, C, Smith, K, Morwood, MJ, Sutikna, T, Jatmiko, WSE, Brunsden, B & Prior, F 2006, ‘Response to comment on "The Brain of LB1, Homo floresiensis"’, Science, vol. 312, p. 999c. doi:10.1126/science.1124972. Falk, D, Hildebolt, C, Smith, K, Morwood, MJ, Sutikna, T, et al. 2007, ‘Brain shape in human microcephalics and Homo floresiensis’, Proceedings of the National Academy of Sciences, vol. 104, no. 7, p. 2513. Falk, D, Hildebolt, C, Smith, K, Jungers, W, Larson, S, Morwood, M, et al. 2009, ‘The type specimen (LB1) of Homo ?oresiensis did not have Laron Syndrome’, American Journal of Physical Anthropology, pp. 1-12. Foley, J 2005, Homo Floresiensis: The Hobbit, viewed 14 January 2011, Hershkovitz, I, Kornreich, L, Laron, Z 2007, ‘Comparative skeletal features between Homo floresiensis and patients with primary growth hormone insensitivity (Laron Syndrome)’, Am. J. Phys. Anthropol., vol. 134, no. 2, pp. 198–208. Jacob, T, Indriati, E, Soejono, RP, Hsu, K, Frayer, DW, Eckhardt, RB, Kuperavage, AJ, Thorne, A & Henneberg, M 2006, ‘Pygmoid Australomelanesian Homo sapiens skeletal remains from Liang Bua, Flores: Population affinities and pathological abnormalities’, Proceedings of the National Academy of Sciences, USA, vol. 103, pp. 13421–13426. Mayell, H 2004, ‘Hobbit-like human ancestor found in Asia’, National Geographic, viewed 14 January 2011, Schalley, AC & Khlentzos, D 2007, ‘Mental States: Evolution, Function, Nature’, illustrated edition, John Benjamins Publishing Company, USA. Weber, J, Czarnetzki, A & Pusch, CM 2005, ‘Comment on "The Brain of LB1, Homo floresiensis"’, Science, vol. 310, no. 5746, p. 236. doi: 10.1126/science.1114789. WorldLingo Translations LLC 2011, Homo Floresiensis, viewed 14 January 2011, Read More